【作者】 任雷厉；

【导师】 江英；

【作者基本信息】 石河子大学 ， 农产品加工及贮藏工程， 2011， 硕士

【摘要】 库尔勒香梨是新疆独特的气候条件造就的优质水果,主要产自新疆维吾尔族自治区南疆地区,尤其以产在巴音郭楞蒙古自治州库尔勒市郊孔雀河畔的最为著名,除此之外,在阿克苏、喀什、和田以及北疆的伊犁河谷一带也有种植。库尔勒香梨具有皮薄肉脆、多汁爽口等特点,堪称梨中的上好佳品,畅销国内外。由于库尔勒香梨在贮藏过程中表皮易产生锈斑,造成了外观品质的下降,给库尔勒香梨的销售带来了很大的影响。鉴于此种情况,本论文以库尔勒香梨表皮锈斑物质为研究对象,对其进行分析鉴定,为香梨果实表皮锈斑物质的生成机理提供理论依据。研究的主要结果如下：1、通过对库尔勒香梨表皮锈斑物质的提取研究可知：乙醇作为提取溶剂,262nm为锈斑提取物的测定波长,响应面分析法优化香梨锈斑物质的提取工艺,确定了各个因素对提取率的影响显著顺序为A(乙醇浓度)>C(浸提时间)>B(液料比)>D(浸提温度)；也确定了最佳提取条件：A(乙醇浓度)=75%、B(液料比)=18：1、C(浸提时间)=4.5h、D(浸提温度)=48℃,此条件下的提取率(以吸光度表示)为0.228。2、通过对库尔勒香梨表皮锈斑物质的分离与纯化可知：香梨锈斑物质乙醇提取液经浓缩,浓缩液加水搅拌后分别用石油醚和氯仿萃取,得到了石油醚部分和氯仿部分。石油醚部分经石油醚-丙酮(4：1)洗脱和石油醚-丙酮(5：1)反复洗脱后,得到了洗脱物1、洗脱物2；氯仿部分经石油醚：乙酸乙酯梯度洗脱后得到的洗脱物分别再用氯仿反复洗脱后得到洗脱物3、洗脱物4、洗脱物5。五种洗脱物分别用薄层色谱和液相色谱进行纯度检验,检验结果表明五种洗脱物都达到了较高的纯度。3、通过对库尔勒香梨表皮锈斑物质的鉴定分析可知：五种洗脱物经化学定性检识、紫外可见光谱扫描定性分析、硅胶薄层色谱定性分析、液相色谱定性分析以及质谱分析鉴定,分析鉴定结果为洗脱物1属于蒽醌类物质中的大黄酸、洗脱物2属于蒽醌类物质中的芦荟大黄素、洗脱物3属于蒽醌类物质中的大黄酚、洗脱物4属于蒽醌类物质中的大黄素、洗脱物5经LC-MS分析含有两种物质,分子量分别为610、624,而且这两种物质中都含有羰基和不饱和共轭体系。由于洗脱物5在香梨表皮锈斑物质中的含量很低和试验条件的限制,所以未对其做进一步分析鉴定。更多还原

【Abstract】 Korla fragrant pear is a high-quality fruit by Xinjiang unique climatic conditions, mainly produced in southern regions of Xinjiang Uygur Autonomous Region, particularly in the middle suburbs Peacock River of Korla in the Yi Autonomous Prefecture of the most famous, in addition, in the Aksu, Kashgar, Khotan and the Ili Valley of the northern area, is also cultivated. Korla fragrant pear with the features of thin Roucui and refreshing juicy, rated enclosed share of pear, sold abroad. As Korla fragrant pear skin is easy to produce rust during storage, caused by the decline in the quality of appearance, to the sale of Korla fragrant pear is a big influence. In view of this, the thesis uses epidermal rust material of Korla fragrant pear as the study object, its analysis and identification provide the theoretical basis for the formation mechanism of Korla fragrant pear epidermis rust material. The main results as follows:1、The extraction study of Korla fragrant pear epidermis rust material shows that:Ethanol as solvent, 262nm for the determination wavelength of rust extract, Response Surface Optimization of pear rust material extraction process, Identified the various factors on the extraction rate was significantly affected by the order of A (ethanol concentration)>C (extraction time)> B (liquid ratio)> D (extraction temperature); The optimum extraction conditions are:A (ethanol concentration)=75%, B (liquid ratio)=18:1, C (extraction time)=4.5h, D (extraction temperature)=48℃, the rate under this Extraction condition (expressed in absorbance) is 0.228.2、The separation and purification of Korla fragrant pear epidermis rust material shows that:Pear rust material ethanol extract is concentrated, after concentrated solution mixing with water, then extracted with petroleum ether and chloroform, has been part of petroleum ether and chloroform.The part of Petroleum ether by petroleum ether-acetone (4:1) elution and petroleum ether-acetone (5:1) repeated elution obtained eluate 1, eluate 2; The part of chloroform by petroleum ether:ethyl acetate gradient elution, then by repeated chloroform elution obtained eluate 3, eluate 4, eluate 5.The purity of five eluate were tested by thin layer chromatography and liquid chromatography,Elution test results show that the five have reached a high purity.3、The identification and analysis of Korla fragrant pear epidermis rust material shows that:Five eluate knowledge by chemical qualitative analysis, UV-visible spectral scanning qualitative analysis, silica gel thin layer chromatography qualitative analysis, liquid chromatography and mass spectrometry qualitative analysis, Identification results for the eluate 1 belonging to the anthraquinone rhein, elution 2 belonging to the anthraquinones aloe-emodin, eluate 3 belonging to the anthraquinones chrysophanol, elution 4 belonging to the anthraquinones emodin, eluate 5 contains two substances by LC-MS analysis, molecular weight of 610、624 and both substances contain carbonyl and unsaturated conjugated system. Because the content of eluate 5 is less in Korla fragrant pear epidermis rust material and limited experimental conditions, So without further analysis identification for eluate 5.更多还原